What are the primary goals of the lake restoration project?
At the onset of this project, initial discussions with members of the community and the Lake Committee produced the following project objectives:
- Restore the lake as a public asset;
- Retain the dam;
- Improve the quality of the lake, specifically overall depth and the fishery;
- Maintain the lake views;
- Improve the functionality of the north channel area;
- Design the restoration project such that activities will be maintainable and sustainable in the long-term with respect to water quality and sedimentation; and
- Design the restoration project within the reality of the current funding situation.
These objectives were used to develop a number of conceptual alternatives that were refined and developed to produce the current design.
What are the main features of the construction?
The project constructed a berm to separate the lake from the river, dredged adjacent to Community Park and within the North Channel area, modified the dam and millrace, and placed dredged sediment to augment the existing islands. The Village’s consultants reviewed all of the studies conducted over the previous 30+ years prior to developing alternative plans.
How deep is the new lake bed in the deepest parts?
It is 8-10 feet in depth in sections, primarily bordering Community Park
How large is the berm?
The berm was designed to look like a rural bike path with low-growing grass surrounding it. It is approximately 20-feet wide at the top, with a 10-foot-wide gravel bike and pedestrian path. The sides slope down to the lake and river at a moderate angle. The top of the berm is approximately 4 to 5.5-ft above the normal water surface of the lake and river. It is 3,130 feet long.
How large is the separated lake area now?
The previous lake area was approximately 94 acres. The major restoration area includes 42 acres of restored lake bed, 11.6 acres of wetlands, and 6.5 acres of floodplain. Additional wetlands have been set aside and more acreage is being acquired. An approximately 30-acre impoundment will remain behind the dam.
How will the berm hold up to seasonal flooding as well as a 100-year event?
The berm was stabilized with vegetation and includes two reinforced overflow sections. Seasonal floods will not overtop the berm and flow velocities are calculated to be low since the dam is immediately downstream. Flood events larger than the 25-year event will overtop the berm, first through the reinforced overflow sections to allow the lake and river levels to equalize, and eventually over the entire berm.
Again, flow velocities are expected to be low since the dam is immediately downstream. Some vegetation, soil, and bike path damage would be expected and would require maintenance.
How will the lake and habitat areas remain in good condition?
The berm and habitat areas will require long-term maintenance to establish and maintain the vegetation, especially the forested areas. The majority of the maintenance work will be in the establishment period within the first three to five years, and includes removing invasive plant species through a variety of methods depending on which species are found. Some supplemental planting of native wetland and tree species will likely be necessary.
The fishery will likely require periodic re-stocking. Carp management will primarily rely on establishing predator fish to keep the carp population in check; infrequent lake draw down’s may be used with WDNR approval to control carp if they become a significant nuisance.
How will the lake be refilled and keep carp from reentering?
The lake is refilled primarily through groundwater. The lake-river connection structure includes a fish screen and two shut-off valves; it is anticipated that use of this structure will not be needed to refill the lake.
What is the current funding situation?
The project construction cost was $2.3 million. Funding sources included $830,000 from the Village lake fund from a 10-year tax levy, $200,000 from a WDNR Stewardship Grant, $150,000 from Dane County, and several large private donations. The Village actively pursues additional federal, state, local funding and grant opportunities. The Village Board will consider whether to borrow funds for any remaining funding shortfall if necessary.
What should I do if I find an injured bird or animal?
Contact the Dane County Humane Society's Four Lakes Wildlife Center for advice. They are dedicated to providing responsible care for the ill, injured and orphaned wildlife of south central Wisconsin, and to promoting education and awareness of the crucial role of wildlife in our community